Mucus is aspirated from the endocervical canal

and sent to the laboratory.

FIG. 13.1: Morphological forms of spermatozoa

404 Concise Book of Medical Laboratory Technology: Methods and Interpretations Measure the volume of the mucus. Evaluate SpinnBarkeit (refers to tenacity of the mucus). Grasp a portion

of mucus with forceps and note the distance, which it

can be drawn before breaking. A good Spinn-Barkeit,

which should prevail at midcycle, is at least 10 cm. A

drop of mucus is then placed on a microscope slide,

covered with a coverslip and examined for the presence

of sperms. An estimate of the number of sperms per high

power field with percentage of motile forms should be

reported. At the same time, look for WBCs, RBCs and

Trichomonas.

Antibodies to Spermatozoa

These can be produced in the male himself or in female.

Role of spermatozoal antibodies in infertility is now an

established fact in experimental studies, but information

pertaining to human spermatozoa is equivocal. Most clinical

correlative studies thus far have utilized sperm agglutination

tests. The method Franklin and Dukes employed makes

use of serum and semen. Results were read (for sperm

agglutination) macroscopically after a 4 hours incubation at

37°C. Some medical diagnostic companies provide kits also

for assessing antibodies to sperms.

14

Sputum Examination

C H A P T E R

SPUTUM

Tracheobronchial secretions are often collectively referred

to as sputum. Sputum is constituted by plasma, water,

electrolytes and mucin. As it comes out, it is contaminated

by nasal and salivary secretions, and normal bacterial

flora of the oral cavity. Under appropriate immunologic

or inflammatory stimulus, mast cells, eosinophils and

plasma cells may contribute to the secretions. Sputum is

viscoelastic, i.e. some of the properties of a liquid. Chemical

composition reveals sputum is 95% water and only 5%

solids. The solid content increases with inflammation. It

also shows exfoliation of lining cells.

Specimen Collection

1. Before collecting or expectorating sputum, the mouth

should be prerinzed and this removes contaminants

from oral cavity especially.

2. For most examinations, a first morning specimen

is best as it represents the pulmonary secretions

accumulated overnight.

3. To obtain a good specimen, patient’s cooperation and

understanding is essential. Usually, no problem arises

with adults. Children are problematic sometimes. The

undermentioned methods can be used for them:

a. A nasopharyngeal swab may be taken which is

quite representative of the bronchial pathogens.

b. A cough plate is held before the child’s mouth

and the child is urged to cough.

c. Cough swab method gives the most representative, noncontaminated sputum sample. The

child’s mouth is held open by using a tongue

depressor. Epiglottis is visualized and is touched

with a swab to induce cough. Material expelled

from trachea is (coughed) deposited on the swab,

which can then be plated on appropriate culture

media.

d. In patients who are uncooperative or cannot

produce adequate sputum, induction should

be tried. Commonly used inductants are 10%

sodium chloride, acetylcysteine and sterile

or distilled water aerosols. In persons with a

history of bronchospasmodic disorders, bronchodilators should be given after inductants are

used. Acetylcysteine breaks the disulfide bonds

which maintain the gel structure of mucus. Acetylcysteine can be given in an aerosol form with a

bronchodilator.

The specimen should be collected in a sterile disposable,

impermeable container with a screw cap.

Sputum Examination

Transfer the specimen in a sterile petridish placed against

a dark background. Wooden applicator sticks can be used

to spread it thinly and can be seen with the naked eye or by

using a hand lens.

Macroscopic Examination

Volume: A 24-hour volume of sputum is measured in

patients with chronic bronchitis, lung abscesses or

bronchial asthma. A rising volume or decreasing volume

indicates worsening and improvement respectively.

Consistency and Appearance

Sputum may be described as serous (liquid), mucoid,

purulent, bloody or combinations of these, e.g. seropurulent, mucopurulent.

A normal sputum is clear and watery and any

opalescence is because of cellular material suspended

406 Concise Book of Medical Laboratory Technology: Methods and Interpretations

in it. In pulmonary edema, sputum is serous, frothy and

blood tinged. Most opaque particles are masses of pus and

epithelium. Other materials seen in the sputum can be

Curschmann’s spirals, Dittrich’s plugs, casseous material,

bronchial casts, or food substances.

Color: Normal sputum is clear and colorless. A Yellow color

indicates pus and epithelial cells as seen in a pneumonic

process.